This application claims the priority of German patent application Serial No. 198 57 296.4 filed Dec. 14, 1998. The disclosure of the above-referenced German patent application, as well as that of each US and foreign patent and patent application mentioned in the specification of the present application, is incorporated herein by reference.
The present invention relates to improvements in methods of and apparatus for making rod-shaped articles of the tobacco processing industry. Such articles include plain and filter cigarettes, cigars, cigarillos and analogous smokers"" products. More particularly, the invention relates to improvements in methods of and apparatus for making a continuous rod wherein a tubular wrapper of cigarette paper or the like surrounds a rod-like filler consisting at least in part of a smokable material. Still more particularly, the invention relates to improvements in methods of and in apparatus for making a continuous rod wherein a tubular wrapper surrounds a rod-like filler containing comminuted smokable material (such as shreds or other fragments of natural, reconstituted and/or substitute tobacco) as well as one or more additives. Typical examples of rod-shaped smokers"" products which can be made in accordance with the method of and in the apparatus of the present invention are plain or filter cigarettes and, therefore, the following disclosure will refer primarily to the making of a rod which can be divided into plain cigarettes; however, it is to be understood that the improved method and apparatus can be resorted to with equal or similar advantage in connection with the making of all or practically all other rod-shaped smokers"" products.
It is already known to contact a rod-like filler of tobacco with an additive prior to draping of the filler into a web of cigarette paper or other suitable wrapping material, i.e., prior to completion of the making of a cigarette rod which is ready to advance through a suitable severing device (known as cutoff) which repeatedly cuts across the leader of the advancing cigarette rod to thus form a file of plain cigarettes of unit length or multiple unit length. Plain cigarettes of unit length are or can be transported directly to a packing machine. Plain cigarettes of multiple unit length are transported to a so-called tipping machine which serves to turn out filter cigarettes.
The aforementioned additive is or can be a liquid additive which is sprayed onto or otherwise contacted with the running rod-like filler of shredded and/or otherwise comminuted natural, reconstituted and/or artificial tobacco. As a rule, a liquid additive can constitute an aerosol or an aromatic substance such as menthol. If the additive is a volatile substance, it is preferably caused to contact the smokable material shortly or immediately prior to draping of the filler into cigarette paper or other suitable wrapping material; this reduces the likelihood of evaporation of high percentages of such substances.
It is also known to make the smokable constituent (i.e the fibrous filler or the fibrous part of the filler) of two or more combustible smoke-generating constituents. Reference may be had, for example, to commonly owned U.S. Pat. No. 4,703,764 granted Nov. 3, 1987 to Siegfrid Marquardt et al. for xe2x80x9cMETHOD AND APPARATUS FOR MAKING ROD-LIKE FILLERS FROM SEVERAL TYPES OF FIBROUS MATERIALxe2x80x9d.
An object of the invention is to provide a novel and improved method of introducing into the smokable part of a rod-like filler for the making of cigarette rods or the like one or more additives in such a way that each additive is uniformly distributed from end to end of each individual cigarette or an analogous rod-shaped smokers"" product embodying a portion of the filler.
Another object of the invention is to provide a novel and improved method of introducing volatile additives into a rod-like filler which is to form part of a cigarette rod or the like.
A further object of the invention is to prevent evaporation of volatile additives (such as one or more aerosols and/or aromatic substances) prior to confinement of a rod-like filler, which contains such additive(s); in a wrapper of cigarette paper or the like.
An additional object of the invention is to provide a method which renders it possible to alter the quantities of one or more additives per unit length of a rod-like filler which is to form part of a continuous cigarette rod or the like.
Still another object of the invention is to provide a method which exhibits the above-enumerated advantages but can be practiced by resorting to relatively simple and inexpensive yet reliable apparatus.
A further object of the invention is to provide the apparatus with novel and improved means for manipulating volatile additives which are to influence the characteristics (such as aroma) of rod-shaped smokers"" products.
Another object of the invention is to provide the above outlined apparatus with novel and improved means for feeding and manipulating the combustible tobacco smoke generating constituents of a cigarette rod filler in a plurality of stages preparatory and subsequent to introduction of one or more volatile additives.
An additional object of the invention is to provide the apparatus with novel and improved means for manipulating encapsulated volatile additives.
Still another object of the invention is to provide a cigarette rod making machine which embodies one or more apparatus of the above outlined character.
A further object of the invention is to provide an apparatus which is constructed and assembled in such a way that it can reliably confine evaporable liquid additives by guaranteeing that those characteristics of the rod-shaped smokers"" products which are attributable to the presence of one or more additives remain at least substantially unchanged irrespective of the duration of storage prior to actual lighting of the products.
Another object of the invention is to provide rod-shaped smokers"" products which are produced in accordance with the above outlined method.
A further object of the invention-is to provide the above outlined apparatus with novel and improved means for manipulating spherical capsules for evaporable additives prior to confinement in comminuted smokable material.
One feature of the present invention resides in the provision of a method of making a smokable filler, e.g., a filler which is ready to be draped into a web of cigarette paper or other suitable wrapping material and to be thus converted into a cigarette rod adapted to be subdivided into plain cigarettes of unit length or multiple unit length.
The improved method comprises the steps of building a first flow (e.g., a relatively thin layer) of a smokable first particulate material and advancing the first flow lengthwise in a predetermined direction along a predetermined path wherein the flow has a side which is accessible in a first (upstream) and in a second (downstream) portion of the predetermined path, delivering to the aforementioned side of the advancing first flow particles of a second particulate material in the first (upstream) portion of the predetermined path, applying to the aforementioned side of the advancing first flow a second flow (e.g., a relatively thin layer) containing the first material (i.e., a material which is smokable) and overlying the particles of the second material (the applying step is carried out in the aforementioned second (downstream) portion of the predetermined path), and converting the first and second flows (and the particles of second material between such flows) into a rod-like filler wherein the particles of second material are at least substantially surrounded by the first material.
The first particulate material contains (or can contain) comminuted tobacco, e.g., shredded natural tobacco leaves, shredded and/or otherwise comminuted sheets of reconstituted tobacco and/or fragments of artificial tobacco.
The second particulate material can consist of or contains aromatic substances and/or aerosols. It is presently preferred to employ a second material in the form of spheres or analogous configurations (e.g., lenses, tablets or the like).
The delivering step can include introducing into the first portion of the predetermined path metered quantities of second particulate material per unit length of the rod-like filler, per unit length of the first flow, or per unit of time (e.g., when the first flow is being advanced at a constant speed).
In accordance with a presently preferred embodiment, the delivering step can include gathering articles of second particulate material into at least one series such as an elongated file or row) of advancing particles, and admitting into the first (upstream) portion of the predetermined path successive particles of the at least one series. The just mentioned gathering step can include establishing an accumulation of second particles (i.e., particles of second particulate material) in random distribution (such as in a pile or heap), subjecting the accumulation to the action of centrifugal force to thus propel particles of second particulate material into a substantially circular path, and conveying particles of second particulate material along the substantially circular path toward and into the first (upstream) portion of the predetermined path. The conveying step can include maintaining the particles of second particulate material in an at least substantially horizontal plane. The just described embodiment of the improved method preferably further comprises the step of at least intermittently replenishing the accumulation of such particles to thus maintain the quantity of particles in the accumulation above a predetermined threshold value.
The advancing step can comprise maintaining the first flow in a state of suspension by suction (e.g., at the underside of the horizontal lower reach of an endless foraminous belt which travels along the open underside of a stationary suction chamber). The aforementioned side of the first flow is then the underside of the pneumatically (suctionally) suspended first flow. The delivering step then preferably comprises attracting the particles of second material to the underside of the first flow by suction (i.e., by the:expedient of maintaining the first flow in suspended condition),so that the particles of second material share the movement of the first flow along the predetermined path. Another
Another feature of the present invention resides in the provision of an apparatus for making a smokable filler. The apparatus comprises means for building a first flow (such as a relatively thin and relatively narrow layer) of a smokable first particulate (e.g., shredded) material including means for advancing the first flow lengthwise in a predetermined direction along a predetermined path wherein the first flow has a side which is accessible in a first (upstream) as well as in a second (downstream) portion of the predetermined path, means for delivering to the aforementioned side of the advancing first flow particles of a second particulate material in the first (upstream) portion of the predetermined path, means for applying to the aforementioned side of the advancing first flow a second flow (e.g., a second relatively thin and relatively narrow layer) containing the first or an equivalent material and overlying the particles of the second material (the applying means is arranged to supply particles of second material into the second (downstream) portion of the predetermined path), and means for converting the first and second flows (as well as the particles of second material between the two flows) into a rod-like filler wherein the second material is at least substantially surrounded by the first material.
The first material can contain shredded and/or otherwise comminuted tobacco leaf laminae, fragments of tobacco ribs, fragments of sheets of reconstituted tobacco and/or fragments of artificial tobacco.
The delivering means can comprise a suitable receptacle for an accumulation of particles of second material in random distribution, means for conveying at least one series (such as a file or a row) of particles of second material along a second path Extending to the first (upstream) portion of the predetermined path, and means for transferring particles of second material from the receptacle into the second path. The transferring means of such apparatus can comprise means for converting a portion of the accumulation of particles of second material in the receptacle into successive increments of the at least one series of particles of second material. The second path can constitute or resemble an at least substantially circular path, and the converting means can comprise means for circulating the accumulation in the receptacle about a predetermined axis to thus subject at least the aforementioned portion of the accumulation to the action of centrifugal force with attendant entry of particles of second material into the second path. The circulating means can comprise means for rotating the receptacle and the particles of second material in the receptacle about an at least substantially vertical axis. The receptacle has at least one outlet for particles of second material, and such at least one outlet is normally remote from the at least substantially vertical axis and is arranged to receive particles of second material under the action of centrifugal force and to admit the thus received particles of second material into at least one inlet of the second path.
The conveying means can be provided with discrete pockets (such as tooth spaces in the marginal portion of a spur gear) for particles of second material.
The receptacle is or can be arranged to rotate about an at least substantially vertical axis and can include a circular bottom wall and an annular sidewall diverging radially of the vertical axis and downwardly toward the bottom wall. The receptacle is provided with at least one outlet for the particles of second material, and such at least one outlet is provided between the bottom wall and the sidewall. For example, the outlet can constitute an arcuate slot. It is preferred to provide the receptacle with an annular array of discrete outlets for particles of second material between a marginal portion of the bottom wall and a bottom portion of the sidewall. At least some of the outlets preferably have elliptical outlines and the major axes of such elliptical outlines are or can be at least substantially tangential to the bottom wall of the receptacle.
It is often preferred to employ in the improved apparatus transferring means which comprises a rotary circular disc having a marginal portion including alternating teeth and tooth spaces. The tooth spaces provide outlets for admission of particles of second material into the second path. The receptacle is rotatable about an at last substantially vertical axis and includes a bottom wall adjacent and located above the disc. The second path extends from the marginal portion of the disc to the first (upstream) portion of the predetermined path. Such apparatus can further comprise a first guide which is located below the disc and a second guide which surrounds the disc and defines with the first guide a means for confining particles of second material in the tooth spaces during a predetermined stage of advancement of particles of the second type with the disc. The guides are preferably stationary and flank the tooth spaces in the direction of the axis of rotation of the disc.
The radius of the bottom wall of the receptacle is or can be smaller than the radius of the disc, and the disc is preferably rotatable about a second axis which is spaced apart from and parallel to the rotational axis of the receptacle. The at least one outlet of the receptacle is arranged to admit particles of second material from the accumulation in the receptacle into the tooth spaces of the disc, and such tooth spaces serve to convey particles of second material from the at least one outlet of the receptacle to the first (upstream) portion of the predetermined path.
The improved apparatus can further comprise means for rotating the receptacle at a first speed, and the advancing means can be arranged to advance the first flow along the predetermined path at a second speed which at least approximates the first speed. Still further, the improved apparatus can comprise means for rotating the receptacle and the disc at different speeds or for rotating the receptacle and the disc at speeds which at least closely approximate each other.
If the first flow is a layer of tobacco shreds having first and second marginal portions which are or can be equidistant (i.e., parallel) to each other, the delivering means can include means for supplying to the aforementioned side of the first flow (layer) particles of second material at least substantially midway between the marginal portions of the first flow.
The delivering means can include means for introducing into the predetermined path metered quantities of particles of second material per unit length of the first flow.
As already mentioned hereinabove, the particles of second material can constitute or resemble spheres. This is often desirable for convenience of mass production of such commodities as well as because such particles can be readily manipulated in the improved apparatus, e.g., to form one or more rows which are advanced lengthwise toward the first (upstream) portion of the predetermined path for convenient and highly predictable introduction into the predetermined path. Moreover, spherical particles of second material can be readily manipulated in order to ensure, that each and every successive unit length of the filler can contain identical numbers of particles of second material, i.e., identical percetages of volatile and/or other substances (such as menthol) in each of a short or long series of unit lengths of the finished filler.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved apparatus itself, however, both as to is costruction and the modes of making, assembling and manipulating the same, together with numerous additional important and advantageous features and attributes thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawings.